The Deltic (after the Greek letter Delta) diesel was a supercharged, two-stroke, opposed-piston engine with no valves. The engine block was arranged in a triangle of cylinder banks forming the sides. ... Built in this three-sided configuration, the Deltic diesel featured six banks of pistons working the three crankshafts.

How many cylinders does a Deltic have?

A Deltic is named after the engine configuration, an inverted triangle – similar to an inverted Greek letter Delta. The engine consists of three cylinders arranged as an equilateral triangle.

Are there any Deltics still running?

All operationally preserved Deltics have run in preservation but only five of the six locomotives have run on the mainline; the only engine that has not yet is 55 015 Tulyar. The preserved Deltics that have run on the mainline are as follows: 55 022, 55 002, 55 009, 55 016 and 55 019.